Biologist Frederick vom Saal won a 2010 Heinz Award for his research on industrial chemicals. He’s an expert on a chemical called BPA, or bisphenol A. It’s found in plastics, food cans and sales receipts. Vom Saal said BPA is also found inside the bodies of over 90% of Americans.
Frederick vom Saal: The amount in the average person is about 2 millionths of a gram per liter of blood. A millionth of something may seem like a very small number. But this is a chemical that can cause abnormalities in human cells below a trillionth of a gram, at phenomenally lower levels. This is an extremely powerful sex hormone drug-like chemical.
Vom Saal said studies have shown that, in animals and humans, BPA can cause a problems ranging from brain damage to reproductive dysfunction. His study indicates that BPA is getting inside humans at much higher rates than previously estimated.
Frederick vom Saal: This number may shock you, but the error of exposure based upon what people thought versus what we’re showing is about a thousand fold.
Dr. vom Saal acknowledged that the science around BPA is controversial. The American Chemistry Council says that BPA is safe for use in food and beverage containers and sales receipts.
Frederick vom Saal: Suddenly, we realized instead of just getting this from food, that touching products with bisphenol A could be a huge source of human exposure.
The issue is serious, vom Saal maintained, because fetuses and young children can’t effectively filter BPA out of their systems, and they’re also the most susceptible to permanent damage. In his 2010 collaboration with the Environmental Working Group, Dr. vom Saal found that 40% of the receipt paper they tested contained large amounts of BPA (250 to 1000 times more than you might get from a food source). BPA is used in industry today because it hardens plastics, and also provides what’s sometimes referred to as a “high performance” finish, or coating on materials. Dr. vom Saal explained BPA’s early history.
Frederick vom Saal: This chemical bisphenol A was initially considered for use as a sex hormone drug. It’s actually acts like the hormone produced in a woman’s ovaries, it’s an estrogen. And it’s essentially like a drug in a birth control pill. And some chemists in the 1950’s make plastic out of it.
At the time, they didn’t realize its long term effects, he said. Dr. vom Saal talked more about his 2010 study in Environmental Health Perspectives, which tested how BPA is metabolized by rhesus monkeys and mice. The findings are a little complicated, he said, but what they show is that these animals “clear” or remove BPA from the system in the same way that humans do. EarthSky asked Dr. vom Saal why that’s important.
Frederick vom Saal: What really is important here is the rate at which we get rid of it, so that over 24 hours after 24 hours after being exposed to BPA in the monkey, the mouse and the humans, you have the same amount of BPA being removed from the body whether you’re a human or a mouse. And as a result of that, we can estimate now human exposures based on the findings we have from the study. Because the rate of clearance of the chemical is the same in animals, and in humans.
He said animals and humans are similar in another way.
Frederick vom Saal: We have the United States National Health Survey that relates bisphenol A levels in Americans to diabetes, obesity and heart disease as well as the amounts in women during pregnancy to abnormal behavior and aggressiveness in babies once they’re born. So we have all those findings in people, and they exactly match what has been found in animals studies.
And in animals studies – the type that could never be done on humans, some different things were found:
Frederick vom Saal: We know that at very very low levels in animals, we’re seeing brain damage, reproductive damage, immune damage, diabetes, heart abnormalities, just an incredible array of disease
Dr. vom Saal said that many other countries have found ways to replace BPA in their industrial products. There are alternatives, he explained.
Frederick vom Saal: This is a chemical used in a wide variety of products, and in other parts of the world, alternatives have already been developed that could replace all of its uses that we think pose a hazard to people, at least that we know about. And so one of the messages here is that we really need corporations in the United States to start paying more attention to the health consequences of the chemicals they’re putting into products.
Japan, for example, eliminated BPA from its food cans a decade ago.
Beth Lebwohl researches, writes and helps produce science content in audio and video formats for EarthSky. She is one of the authors on EarthSky.org, a script-writer for our podcasts, and helps host our English science podcasts in 90-second, 8-minute and 22-minute formats. Beth came to EarthSky in 2006 from the American Museum of Natural History's Department of Astrophysics, where she was surrounded by some of the greatest telescope-building, equation-wielding, code-writing physicists of our time. And they made her think . . . this science thing . . . it's pretty cool.